1. Field of the Invention
Embodiments of the disclosure relate to a gamma tab voltage generator.
2. Discussion of the Related Art
Flat panel displays such as a liquid crystal display and an organic light emitting diode (OLED) display convert a data voltage into a gamma compensation voltage and supply the gamma compensation voltage to pixels of a display panel. The OLED display has a self-emission structure in which an OLED is formed in each pixel of the display panel.
The gamma compensation voltage is set along a nonlinear curve. The nonlinear curve is divided into several steps, so that the gamma compensation voltage is implemented along the nonlinear curve. Voltages of each step are set to gamma tab voltages (or gamma reference voltages). A gamma integrated circuit (IC) generates the gamma tab voltages using a plurality of buffers. The buffers are generally designed to have a maximum current capacity capable of generating a maximum gamma tab voltage irrespective of a difference between the gamma tab voltages. Because of this, the related art gamma IC includes the plurality of buffers having an unnecessarily large current capacity. Thus, power consumption and an amount of heat generated in the related art gamma IC increase, and the size of the related art gamma IC increases.
The gamma IC commonly supplies the gamma tab voltages to source driver ICs of a data driving circuit. Because the gamma IC has a fixed buffer capacity, extensibility and compatibility of the gamma IC are reduced. Thus, it is difficult for the related art gamma IC to cope with changes in a resolution of the display panel. For example, when the number of source driver ICs increases due to an increase in the resolution of the display panel, the gamma IC has to output a current equal to or greater than the maximum current of the gamma IC. Thus, the gamma IC has to be newly designed.